<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title>原始数据类型</title>
</head>
<body>
<script>

    var a = 200;   //整型 Number
    var b = 92.5;   //浮点型 Number
    var c = "I'm String";   //字符串型 String
    var d = true;   //布尔类型
    var e;    //undefined型
    var f = null;   //object型
    alert(typeof c);

</script>
</body>
</html>